Rotary valve

Abstract

A concentric rotary valve having a rotatable stem of a valve disc supported by bearing portions and metal seats mounted in a valve housing to contact metal seats on the valve disc. Clearances in directions parallel to a closed disc surface and radial of the valve stem are barely enough to permit a shift of the valve disc to provide a good seat-to-seat contact when the valve is closed, and clearances in directions normal to the closed disc surface and radial of the rotatable stem are barely enough to permit normal rotations of the stem.

I claim: 
     
       1. A rotary valve comprising: a housing having an inlet and an outlet;   bearing means supported on an axis of said housing;   a rotatable valve stem supported by said bearing means;   said rotary valve stem including bearing surfaces juxtaposed said bearing means;   a valve disc coaxially supported by said valve stem within said housing between said inlet and said outlet;   a valve seat supported by said housing in direct relationship with said valve disc and operative therewith for closing said valve; and   said valve stem bearing surfaces having an outer surface configuration which is different from the inner surface configuration of said bearing means in which one of said surface configurations is a circle and the other of said surface configurations is elliptic-oval shaped which forms a clearance between said valve stem bearing surfaces and said bearing means;   whereby said clearance between said valve stem bearing surfaces and said bearing means is greater in a direction perpendicular with the flow of fluid than in a direction parallel to the fluid flow.   
     
     
       2. A rotary valve as claimed in claim 1, wherein: said bearing means includes bushings; and   the clearance is between said rotatable valve stem bearing surface and said bushing.   
     
     
       3. A rotary valve as claimed in claim 2, wherein: said valve stem bearing surfaces have an elliptic-oval configuration; and   said bearing means has a circular inner surface configuration.   
     
     
       4. A rotary valve as claimed in claim 2, wherein: said valve stem bearing surfaces have a circular configuration; and   said bearing means has an inner surface configuration of an elliptic-oval shape.   
     
     
       5. A rotary valve as claimed in claim 1, wherein: said valve stem bearing surface includes a bushing thereon in the area of said bearing means; and   said bearing means includes a tubular means.   
     
     
       6. A rotary valve as claimed in claim 5, wherein: said bushing has an elliptic-oval configuration; and   said tubular means has a circular configuration.   
     
     
       7. A rotary valve as claimed in claim 5, wherein: said bushing has a circular configuration and said tubular means has an elliptic-oval configuration.   
     
     
       8. A rotary valve as claimed in claim 1, wherein: said valve stem bearing surface includes a bushing and a tubular means thereon in the area of said bushing means;   and said bushing means includes a bearing portion.   
     
     
       9. A rotary valve as claimed in claim 8, wherein: said tubular means on said valve stem has an elliptic-oval configuration; and   said bearing portions have a circular configuration.   
     
     
       10. A rotary valve as claimed in claim 8, wherein: said tubular means on said valve stem has a circular configuration; and   said bearing portions have an elliptic-oval configuration.